Barnaslingan (Irish: Barr na Slinneán, meaning 'summit of the shoulder blades') is a 238 metres (781 feet) high hill in County Dublin, Ireland. It is most noted for the geological feature known as The Scalp (Irish: An Scailp, meaning 'the chasm' or "cleft") that lies to the west of the summit. Samuel Lewis, in A Topographical Dictionary of Ireland (1837), described it thus: “A deep natural chasm in the mountain, forming a defile with lofty and shelving ramparts on each side, from which large detached masses of granite many tons of weight have fallen, on each side large masses of detached rock are heaped together in wild confusion, apparently arrested in their descent, and threatening at every moment to crush the traveller by their fall”.